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A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 vanluongkma 5730
#2 deborahajewole 2870
#3 leezy 2100
#4 naylor0 1905
#5 DrUmar 1580
Recent Solves
Great Snakes ezemagnatta
You either know, XOR you don't Remus
XOR Properties eucleto
XOR Starter Banananas
Passwords as Keys sdotimp
Recent Solutions
Quadratic Residues Nosiume 0
Modular Binomials pcman 0
Adrien's Signs pcman 0
Chinese Remainder Theorem pcman 0
Modular Square Root pcman 0

Level Up

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